The man who carried out the deadly knife attack in central Paris on Saturday night was born in Chechnya in 1997, and his parents have been detained for questioning in the investigation, French authorities said Sunday.
A judicial official said the attacker had French nationality but was born in the Russian republic of Chechnya, where Islamic extremism has long simmered. The official said the man had no record of arrests or convictions but had been on the police radar for radicalism, and had been on a nationwide database of thousands of people suspected of links to radicalism.
The knife-wielding attacker killed a 29-year-old man and wounded four other people around 9 p.m. on Rue Monsigny, in a bustling neighborhood near Paris' famed Palais Garnier opera house, before he was killed by police.
The Islamic State group claimed the attacker was one of its "soldiers."
Counterterrorism authorities have taken charge of the investigation.
French President Emmanuel Macron vowed that France, which has been the target of multiple lethal attacks in recent years, would not bow to extremists.
Paris police officers evacuated people from some buildings in the neighborhood after the attack. Bar patrons and operagoers described surprise and confusion in the immediate area.
Beyond the police cordon, however, crowds still filled nearby cafes and the city's nightlife resumed its normal pace soon after the attack.
The attacker targeted five people and then fled, according to Paris police and a witness. When police arrived minutes later, the attacker threatened them and was shot to death, according to police union official Yvan Assioma.
Prosecutor Francois Molins said counterterrorism authorities are leading the investigation as a case of terrorism involving murder and attempted murder.
"At this stage, based on the one hand on the account of witnesses who said the attacker cried 'Allahu akbar' ['God is great' in Arabic] while attacking passersby with a knife, and given the modus operandi, we have turned this over to the counterterrorism section of the Paris prosecutor's office," Molins told reporters at the scene.
The Islamic State group's Aamaq news agency said in a statement early Sunday that the assailant carried out the attack in response to the group's calls for supporters to target members of the U.S.-led military coalition squeezing the extremists out of Iraq and Syria.
The Aamaq statement did not provide evidence for its claim or details of the assailant's identity.
France's military has been active in the coalition since 2014, and Islamic State adherents have killed more than 200 people in France in recent years, including the 130 killed in the coordinated attacks of November 2015 in Paris.
Macron tweeted his praise for police who "neutralized the terrorist" and said, "France is once again paying the price of blood but will not cede an inch to enemies of freedom."
France's BFM television interviewed an unnamed witness in a restaurant who said a young woman had been standing at the entrance when "a man arrived and attacked her with a knife." A friend came to her aid and the attacker left, "hitting on all the doors, all the shops," the witness said. He turned onto another street, and everyone scattered, the witness said.
Another witness, identified only as Gloria, said she had been in a nearby bar.
"I was having a drink with friends and we heard a boom," she said. She said she went outside to see what happened and "saw a guy lying on the ground."
Another witness described leaving the opera house and being told to go back inside because of the attack.
The interior minister said the lives of the four wounded people were no longer in danger.
French Prime Minister Edouard Philippe said it took police less than nine minutes to subdue the attacker from the moment they were alerted.
"This speed, calm and effectiveness allowed them to avoid ... a much heavier toll," he told reporters.
French police have been criticized in the past for failing to prevent attacks.
Paris authorities called for calm and understanding.
"Whatever the motivations of this odious act, let us remain united and standing," Deputy Mayor Bruno Julliard tweeted.
